sputters up top

heres the prob: today I just put on a single pedel polini blue reed with a #72 jet on my cag, when it reaches 8600 rpm it starts to sputter. I tried #68 jet before that and same thing happened. when i had the stock reeds i got to 9500rpm. Does anyone know whats up? Before and after i had a big bore motor, just to put that in so i am not going from stock to big bore.

Could be a few things, you need to play to see what works.

Firstly the blue reeds are too thin for a CAG, thay flutter at to rev's. YOu need to use the green reeds, I am using them with no problems. If after changing to the green reed or stiffer reed than the blue it is still bogging at top rev's, then you need to play with the jets,also the rich/lean setting on the needle (if you are using a standard carb). It is probably too rich or too lean, only testing different jets will tell you the answer.

I am running a Yellow Jacket copy BBK, BZM single reed (same stiffness as the Pollini green), cut out the centre brace on the reed cage, 19mm Del' orto replica carb and Jet Pro pipe. Bike flies, its awesome.

Read your plug for a rich or lean condition.If the plug is a nice brown color.Its your reed.Too thin reed you will get a top end flutter.The ada f/g reed has been the best I have tested.Even performed better than the b/w 3 stage.The b/w split on 1 peddle in less than 10 mins of run time.Performance with noticeable gains and longevity.ADA F/G RACING REED.Jet your carb aprop and the ada will be more than enough.A thin reed would have gains on a short tight track if geared correctly.Thin reeds and top end rpms do not go hand in hand.I used the b/w 3 stage peddles on the ada.Took some time to dial in the jetting.But that worked great with my combo for a mid to open track.fcsc bbk fully ported 53.4 cc's with adj clutch 6/60 gearing with pac sales fatty pipe boosted 306 swirl ported carb with stack..

alright, i will try the green reed today and see if that helps. i thought that there was only an idle screw on the stock cag carb which does nothing for top end? i changed my jets and it still bogged up top, so I am thinking its the reed.

ok i tried the green, and well same thing happened, around 8400rpm it starts to bog, then i adjusted the throttle clip. it didnt run. then i took off the bottom engine ring and it just sucks. could it be that i am running to big of a jet? If i am why does it idle but suck up top?

The only way to tell if your running too big of a jet is to do plug/chop. Your plug will let you know if your running to lean or rich. A nice carmel brown is what you want.

i think your jetted to low, try a bigger jet, but the only way to tell for sure is if you do a plug chop

i went with the biggest one. I know what was wrong, the petcock was not flowing well so i kinda did the petcock mod just without the jb weld. this is with the green reeds it got to 9700 rpm but it takes forever. It is also a pain to start, is that just the reed or is something else wrong.

ok, so i put in the blue reed, and it ran like a champ, it has to be started from choke when cold but thats fine. now i need an exhaust for 2 reasons: 1. i can only get to 9700rpm and i need more flow. 2. it exhaust snapped in 2, so i will re-weld this one and wait till i buy a pbu race pipe.

well the poline green reed is hardeer to start because it is thicker, but if the blue worked better for you, then just keep the blue, good choice on the PBU Race Pipe